FAQs

FAQs

We have answered some frequently asked questions below. Please contact your Centek Product Service Expert for more information. 

Can you use Centek stop collars with non-Centek centralizers and Centek centralizer with non-Centek stop collars?

Our products are developed to work in conjunction with each other and we are unable to guarantee the performance of either our stop collars or centralizers with another company's product. In the event of an issue we would be unable to ascertain which product was at fault.

Does adding more centralizers to the string increase drag?

No...not with our flexible single piece centralizers. In fact up to a point the more centralizers you use the lower the drag. See example below:

Can I rotate with Centek single piece bow spring centralizer?

Absolutely! Centek single piece bow spring centralizers are strong enough to stand up to the rotational torque of casing rotation and have a low enough coefficient of friction to allow the casing to rotate freely inside the centralizers. Here the centralizer is acting as a sleeve bearing. Read more...

Can I use a Centek single piece bow spring centralizer in ERD wells?

Extended-reach drilling (ERD) wells are becoming more common in the industry in order to produce reservoirs in a more economical way. However, there are numerous challenges associated with design and construction of these wells, such as directional drilling optimization, equivalent circulation density (ECD) limitations, and casing running issues. Centek premium single piece, bow spring centralizers are developed to perform in ERD wells. This is due to their inherent strength and engineered flexibility. Read more...

Do all centralizer manufacturers test their products in the same way?

The short answer is 'no'. Even with API 10D regulations, we know competitors do not test in the same way. This will be exacerbated by the removal of the monogram programme by the API. We can tell you that in our side by side comparison testing, on our own S2 product and competitor products targeted at the same applications, the results were conclusive, highlighting the superior performance of the S2. Testing also indicated that many competitor products did not perform to the claims of their datasheets. See the test results...

Can I rotate casing with the tight tolerance single piece bow spring centralizers?

Yes, TUR and UROS centralizers are designed to allow rotation of the string, even when fully compressed. We have case studies which prove this.

Are Centek tight tolerance single piece bow spring centralizers built to last if the casing needs to be pushed in the well?

UROS and TURs are tight tolerance centralizers which means they have a high flexibility rating compared with the regular bows springs, so 'yes', they are designed to be pushed.

Why is it important to use the recommended quantity of centralizers?

Our simulation software accurately predicts the quantity of centralizers needed to achieve the desired stand-off. Deviation from this can dramatically reduce the stand-off, often to below the API performance standard.

How does drag compare between the UROS and the TUR?

The drag force with the UROS will be reduce compared with the TUR. In the following chart, the difference can be seen between the axial load required to pass through the same restriction.

Drag comparison between Centek TUR and UROS

What does restoring force mean?

Restoring force is the force required to suspend the pipe and push it away for the casing or wellbore wall. Centek bow spring centralizers have high restoring forces due to the steel used, our unique manufacturing process and innovative heat treatment process.

What does stand-off mean?

The term stand-off (SO) describes the extent to which the pipe is centered, A standoff of 0% means that the pipe touches the wellbore. Regardless of the centralizer type, the goal is to provide a positive standoff, preferably above 67%, throughout the casing string. Stand-off can be predicted using our proprietary Latload system.

What are start and running forces?

Starting force is the force required to displace the centralizer through a restriction and can drastically change based on how the centralizer is held on the pipe. Running force is the force required to displace the centralizer inside of a restriction once it is compressed. Many of our products have zero or low start and running forces.

What is the chordal drop on a Centek single piece centralizer?

The chordal drop is a cross curvature added to each bow on many of the single piece centralizers in our bow spring range. This reduces the contact area with the wellbore walls, easing run-in-hole (RIH)

Where are Centek products manufactured?

We have manufacturing plants in USA, UK and China. Find out more...

How do I purchase a Centek product?

Our products are only available through our network for distributors. For more information contact sales@centekgroup.com